The 73-year-old Leawood, Kan., woman and her two sisters waited until their parents and two other family members had died before contacting cold case detectives in March and asking them to reopen their sister's December 1975 death.

“I said, ‘Let's see if they've done any DNA testing on her,'” Roscoe recounted. “We all three agreed to it.”

Detectives looked into the case, which had been handled by the Oklahoma County sheriff's office. They gathered some old evidence, ran some tests and found a DNA match to a convicted rapist serving six life terms.

On Tuesday, Oklahoma County prosecutors charged Thomas Levering, 62, with first-degree murder in Watson's strangulation slaying, after DNA evidence linked him to the crime.

Levering was convicted in March of attacking, kidnapping and raping an Oklahoma City woman and is serving six consecutive life sentences.

Earlier convictions

He pleaded guilty in 1979 to two other sexual assaults and served 29 years of a 60-year sentence before being paroled in 2008.

Levering told homicide detectives he met Watson at Shepherd Mall but provided no other details, according to a probable cause affidavit.

Watson's decomposing body was found Dec. 30, 1975, in a wooded area in far northwest Oklahoma County.

The 38-year-old bank clerk had been strangled with a piece of nylon hosiery, police reported.

Shortly after her disappearance was reported, officers found Watson's unlocked car parked at Penn Square Mall.

A couple told police they last saw her Dec. 8 at Crossroads Mall.

A girl discovered her purse Dec. 14 inside a trash bin in the 4800 block of Classen Boulevard

Toll on parents

Nobody took Watson's death harder than her parents, who died within a few months of each other in 2000.

“I think it affected them until the day they died,” Roscoe said Wednesday by phone. “We got through it the best we could. We did what we could for our parents. Anytime you lose a child, it's tragic, no matter how they pass away.”

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by Tim Willert

Education Reporter

Tim Willert is a native Californian with Oklahoma ties who covers education. Prior to moving to Oklahoma in June 2011, he was as an editor for FOXSports.com in Century City, Calif., and reported on courts for the Los Angeles Daily Journal and...